rtcp/receiver_report/
mod.rs

1#[cfg(test)]
2mod receiver_report_test;
3
4use std::any::Any;
5use std::fmt;
6
7use bytes::{Buf, BufMut, Bytes};
8use util::marshal::{Marshal, MarshalSize, Unmarshal};
9
10use crate::error::Error;
11use crate::header::*;
12use crate::packet::*;
13use crate::reception_report::*;
14use crate::util::*;
15
16type Result<T> = std::result::Result<T, util::Error>;
17
18pub(super) const RR_SSRC_OFFSET: usize = HEADER_LENGTH;
19pub(super) const RR_REPORT_OFFSET: usize = RR_SSRC_OFFSET + SSRC_LENGTH;
20
21/// A ReceiverReport (RR) packet provides reception quality feedback for an RTP stream
22#[derive(Debug, PartialEq, Eq, Default, Clone)]
23pub struct ReceiverReport {
24    /// The synchronization source identifier for the originator of this RR packet.
25    pub ssrc: u32,
26    /// Zero or more reception report blocks depending on the number of other
27    /// sources heard by this sender since the last report. Each reception report
28    /// block conveys statistics on the reception of RTP packets from a
29    /// single synchronization source.
30    pub reports: Vec<ReceptionReport>,
31    /// Extension contains additional, payload-specific information that needs to
32    /// be reported regularly about the receiver.
33    pub profile_extensions: Bytes,
34}
35
36impl fmt::Display for ReceiverReport {
37    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
38        let mut out = format!("ReceiverReport from {}\n", self.ssrc);
39        out += "\tSSRC    \tLost\tLastSequence\n";
40        for rep in &self.reports {
41            out += format!(
42                "\t{:x}\t{}/{}\t{}\n",
43                rep.ssrc, rep.fraction_lost, rep.total_lost, rep.last_sequence_number
44            )
45            .as_str();
46        }
47        out += format!("\tProfile Extension Data: {:?}\n", self.profile_extensions).as_str();
48
49        write!(f, "{out}")
50    }
51}
52
53impl Packet for ReceiverReport {
54    /// Header returns the Header associated with this packet.
55    fn header(&self) -> Header {
56        Header {
57            padding: get_padding_size(self.raw_size()) != 0,
58            count: self.reports.len() as u8,
59            packet_type: PacketType::ReceiverReport,
60            length: ((self.marshal_size() / 4) - 1) as u16,
61        }
62    }
63
64    /// destination_ssrc returns an array of SSRC values that this packet refers to.
65    fn destination_ssrc(&self) -> Vec<u32> {
66        self.reports.iter().map(|x| x.ssrc).collect()
67    }
68
69    fn raw_size(&self) -> usize {
70        let mut reps_length = 0;
71        for rep in &self.reports {
72            reps_length += rep.marshal_size();
73        }
74
75        HEADER_LENGTH + SSRC_LENGTH + reps_length + self.profile_extensions.len()
76    }
77
78    fn as_any(&self) -> &(dyn Any + Send + Sync) {
79        self
80    }
81
82    fn equal(&self, other: &(dyn Packet + Send + Sync)) -> bool {
83        other.as_any().downcast_ref::<ReceiverReport>() == Some(self)
84    }
85
86    fn cloned(&self) -> Box<dyn Packet + Send + Sync> {
87        Box::new(self.clone())
88    }
89}
90
91impl MarshalSize for ReceiverReport {
92    fn marshal_size(&self) -> usize {
93        let l = self.raw_size();
94        // align to 32-bit boundary
95        l + get_padding_size(l)
96    }
97}
98
99impl Marshal for ReceiverReport {
100    /// marshal_to encodes the packet in binary.
101    fn marshal_to(&self, mut buf: &mut [u8]) -> Result<usize> {
102        if self.reports.len() > COUNT_MAX {
103            return Err(Error::TooManyReports.into());
104        }
105
106        if buf.remaining_mut() < self.marshal_size() {
107            return Err(Error::BufferTooShort.into());
108        }
109
110        /*
111         *         0                   1                   2                   3
112         *         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
113         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
114         * header |V=2|P|    RC   |   PT=RR=201   |             length            |
115         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
116         *        |                     SSRC of packet sender                     |
117         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
118         * report |                 SSRC_1 (SSRC of first source)                 |
119         * block  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
120         *   1    | fraction lost |       cumulative number of packets lost       |
121         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
122         *        |           extended highest sequence number received           |
123         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
124         *        |                      interarrival jitter                      |
125         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126         *        |                         last SR (LSR)                         |
127         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
128         *        |                   delay since last SR (DLSR)                  |
129         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
130         * report |                 SSRC_2 (SSRC of second source)                |
131         * block  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
132         *   2    :                               ...                             :
133         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
134         *        |                  profile-specific extensions                  |
135         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
136         */
137        let h = self.header();
138        let n = h.marshal_to(buf)?;
139        buf = &mut buf[n..];
140
141        buf.put_u32(self.ssrc);
142
143        for report in &self.reports {
144            let n = report.marshal_to(buf)?;
145            buf = &mut buf[n..];
146        }
147
148        buf.put(self.profile_extensions.clone());
149
150        if h.padding {
151            put_padding(buf, self.raw_size());
152        }
153
154        Ok(self.marshal_size())
155    }
156}
157
158impl Unmarshal for ReceiverReport {
159    /// Unmarshal decodes the ReceiverReport from binary
160    fn unmarshal<B>(raw_packet: &mut B) -> Result<Self>
161    where
162        Self: Sized,
163        B: Buf,
164    {
165        /*
166         *         0                   1                   2                   3
167         *         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
168         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
169         * header |V=2|P|    RC   |   PT=RR=201   |             length            |
170         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
171         *        |                     SSRC of packet sender                     |
172         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
173         * report |                 SSRC_1 (SSRC of first source)                 |
174         * block  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
175         *   1    | fraction lost |       cumulative number of packets lost       |
176         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
177         *        |           extended highest sequence number received           |
178         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
179         *        |                      interarrival jitter                      |
180         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
181         *        |                         last SR (LSR)                         |
182         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
183         *        |                   delay since last SR (DLSR)                  |
184         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
185         * report |                 SSRC_2 (SSRC of second source)                |
186         * block  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
187         *   2    :                               ...                             :
188         *        +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
189         *        |                  profile-specific extensions                  |
190         *        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
191         */
192        let raw_packet_len = raw_packet.remaining();
193        if raw_packet_len < (HEADER_LENGTH + SSRC_LENGTH) {
194            return Err(Error::PacketTooShort.into());
195        }
196
197        let header = Header::unmarshal(raw_packet)?;
198        if header.packet_type != PacketType::ReceiverReport {
199            return Err(Error::WrongType.into());
200        }
201
202        let ssrc = raw_packet.get_u32();
203
204        let mut offset = RR_REPORT_OFFSET;
205        let mut reports = Vec::with_capacity(header.count as usize);
206        for _ in 0..header.count {
207            if offset + RECEPTION_REPORT_LENGTH > raw_packet_len {
208                return Err(Error::PacketTooShort.into());
209            }
210            let reception_report = ReceptionReport::unmarshal(raw_packet)?;
211            reports.push(reception_report);
212            offset += RECEPTION_REPORT_LENGTH;
213        }
214        let profile_extensions = raw_packet.copy_to_bytes(raw_packet.remaining());
215        /*
216        if header.padding && raw_packet.has_remaining() {
217            raw_packet.advance(raw_packet.remaining());
218        }
219         */
220
221        Ok(ReceiverReport {
222            ssrc,
223            reports,
224            profile_extensions,
225        })
226    }
227}